The present invention relates to a rolling device and more particularly to such a device which can be attached to a tractor or like vehicle so as to pick up trays of raisins from the ground, fold in opposite side edges of the trays to encapsulate the raisins, invert the folded trays and return them to the ground in inverted condition.
The manipulating of work objects in agriculture and industry involves a variety of difficulties. For example, the production of raisins involves well known and simple techniques to dry grapes harvested from their vines. Currently the most popular technique is to arrange the grapes on rectangular trays of paper measuring approximately two by three feet spread on the ground between two rows of the vines. The trays and their grapes are then left in the vineyard for preliminary sundrying. After a period of several days, the partially dried grapes are inverted by a procedure known as "turning" and the grapes again exposed to the sun for drying. After drying for the desired interval, the trays are normally rolled by manual labor into what is known as a "cigarette roll" which consists simply in lifting two opposite edges of the tray and folding them towards the center of the tray, one above the other. The entire tray is then inverted and replaced on the ground so that the weight of the folded tray and its contents holds the folded edges closed, encapsulating the raisins so as to be cured for a predetermined period while being somewhat protected from inclement weather. The dried and cured raisins are eventually taken to a packing house for separation, cleaning, stemming and packaging.
The history of the mechanization of agriculture reveals an unrelenting trend of efforts to find replacement for manual labor. In many instances, increasing labor costs where mechanization has not been achieved, has led to the abandonment of crops having high hand labor requirements. In other instances, mechanization has made continued farming of certain crops possible. Raisin production has been exceedingly difficult to mechanize. As a result, many previous raisin farmers now convert their grapes to other uses, such as fresh sales, wine or the like.
It has long been recognized that a need exists for a rolling device which, for example, can be employed to roll paper trays but such need has long resisted practical solution.